Topic 19.6: Calculating the Number of Lots Available for Development >

Learning Objective

After successfully completing this topic, you will be able to calculate the number of lots available for development, given the total number of acres contained in a parcel, the percentage of land reserved for streets and other facilities and the minimum number of square feet per lot.

Building Lot Calculation

This is a basic calculation for developers to estimate how many building sites can be sold in a subdivision. In order to make this calculation, assume the developer shows the following data:
• Total number of acres in the parcel—48 acres.
• The percentage of land that is set aside for streets, parks, and other facilities—28%.
• The minimum number of square feet in a site—8,500.

The developer will have approximately 177 building sites available for sale, calculated as follows
• Number of square feet in 48 acres:48 x 43,560 sq. ft. per acre = 2,090,880 sq. ft.
• Number of square feet taken by roads and parks: 2,090,880 x 28% = 585,446.4.
• Subtract the road and park square footage from the total: 2,090,880 – 585,446.4 = 1,505,443.6 square feet available for sites.
• Number of sites by dividing square feet available for sites by the minimum lot square footage to get the number of sites: 1,505,443.6 ÷ 8500 = 177.11, or 177 lots.